<template>
  <div>
    <div class="app-container">
      <el-form label-width="120px">
        <el-form-item label="讲师名称">
          <el-input v-model="teacher.name"/>
        </el-form-item>
        <el-form-item label="讲师排序">
          <el-input-number v-model="teacher.sort" :min="0" controls-position="right"/>
        </el-form-item>
        <el-form-item label="讲师头衔">
          <el-select v-model="teacher.level" clearable placeholder="请选择">
            <!--
            数据类型一定要和取出的json中的一致，否则没法回填
            因此，这里value使用动态绑定的值，保证其数据类型是number
          -->
            <el-option :value="1" label="高级讲师"/>
            <el-option :value="2" label="首席讲师"/>
          </el-select>
        </el-form-item>
        <el-form-item label="讲师资历">
          <el-input v-model="teacher.career"/>
        </el-form-item>
        <el-form-item label="讲师简介">
          <el-input v-model="teacher.intro" :rows="10" type="textarea"/>
        </el-form-item>

        <!-- 讲师头像 -->
        <el-form-item label="头像上传">
          <pan-thumb :image="teacher.avatar"/>

          <el-button type="primary" icon="upload" @click="imagecropperShow=true">选择头像
          </el-button>

          <image-cropper
            v-show="imagecropperShow"
            :width="300"
            :height="300"
            :key="imagecropperKey"
            :url="BASE_API+'/admin/oss/file/upload'"
            :max-size="2048"
            field="file"
            @close="close"
            @crop-upload-success="cropSuccess"/>
        </el-form-item>

        <el-form-item>
          <el-button :disabled="saveBtnDisabled" type="primary" @click="saveOrUpdate">保存</el-button>
        </el-form-item>
      </el-form>
    </div>
  </div>
</template>

<script>
import teacher from '@/api/edu/teacher'
import ImageCropper from '@/components/ImageCropper'
import PanThumb from '@/components/PanThumb'

const defaultForm = {
  name: '',
  sort: 0,
  level: '',
  career: '',
  intro: '',
  avatar: process.env.OSS_PATH + '/avatar/avatar-boy.gif'
}
export default {
  components: { ImageCropper, PanThumb },
  data() {
    return {
      teacher: {
        name: '',
        sort: 0,
        level: 1,
        career: '',
        intro: '',
        avatar: ''
      },
      saveBtnDisabled: false, // 保存按钮是否禁用,
      imagecropperShow: false,
      imagecropperKey: 0,
      BASE_API: process.env.BASE_API // 动态获取环境中的BASE_API
    }
  },

  watch: {
    $route(to, from) {
      this.init()
    }
  },

  created() {
    this.init()
  },

  methods: {
    init() {
      if (this.$route.params && this.$route.params.id) {
        const id = this.$route.params.id
        this.fetchDataById(id)
      } else {
        // 使用对象拓展运算符，拷贝对象，而不是引用，
        // 否则新增一条记录后，defaultForm就变成了之前新增的teacher的值
        this.teacher = { ...defaultForm }
      }
    },

    saveOrUpdate() {
      this.saveBtnDisabled = true
      if (!this.teacher.id) {
        this.saveData()
      } else {
        this.updateData()
      }
    },

    // 保存
    saveData() {
      teacher.save(this.teacher).then(response => {
        return this.$message({
          type: 'success',
          message: '保存成功!'
        })
      }).then(resposne => {
        this.$router.push({ path: '/edu/teacher' })
      })
    },

    // 根据id查询记录
    fetchDataById(id) {
      teacher.getById(id).then(response => {
        this.teacher = response.data.item
      })
    },

    // 根据id更新记录
    updateData() {
      teacher.updateById(this.teacher)
        .then(response => {
          return this.$message({
            type: 'success',
            message: '修改成功!'
          })
        }).then(resposne => { // 跳转到列表页
          this.$router.push({ path: '/edu/teacher' })
        })
    },

    // 上传成功的回调，data就是响应数据
    cropSuccess(data) {
      this.imagecropperShow = false
      this.imagecropperKey = this.imagecropperKey + 1

      // 从后端获取文件上传的url地址，并赋值给 this.teacher.avatar
      // data 来自后端服务器的返回值
      this.teacher.avatar = data.url
    },

    // 关闭文件上传组件
    close() {
      this.imagecropperShow = false
      // 关闭窗口时，改变组件id，使下一次打开窗口时的组件进行重新渲染
      this.imagecropperKey = this.imagecropperKey + 1
    }

  }
}
</script>
